A WHITE MALE INFANT presented at 3½ months of age with vomiting and weight loss. His symptoms progressively worsened prior to referral at 5 months of age to a pediatric gastroenterologist. His symptoms included daily effortless regurgitation and intermittent projectile vomiting. Radiographic series of the upper gastrointestinal tract (Figure, left) demonstrated a narrowed and elongated pylorus with a multilobular filling defect in the duodenal bulb, associated with delayed gastric emptying. Endoscopic evaluation of the same area showed a markedly swollen and erythematous pylorus with a pinpoint opening. A small polypoid lesion emanating from the antropyloric folds was visualized passing back and forth through the pylorus to the duodenum.
A biopsy specimen of this region revealed eosinophilic infiltration and hyperplasia of the foveolar mucosa. The patient was given a protein hydrolysate formula, and within 2 weeks his vomiting had significantly improved. Repeated radiographic series of the upper gastrointestinal tract (Figure, right)